How can the ground beneath a climbing wall be made safe?
The ground beneath climbing walls in playgrounds must be assessed to BS EN 1176. Where the free height of fall exceeds 60 cm, the entire impact area requires impact-absorbing safety surfacing with a critical fall height, tested to BS EN 1177, at least equal to the free height of fall. Grass and topsoil are taken into account by BS EN 1176 up to a free height of fall of 100 cm, provided the area is maintained and yielding, with no stones, roots, foundations or other hard objects. This condition is not met where the ground is compacted, dried out or frozen.
For greater free heights of fall, loose-fill materials or impact-absorbing safety surfacing tiles may be used. The test report states the critical fall height for a specified construction, including the tile type, thickness and jointing and, for multilayer systems, the complete layer sequence. This value is determined in laboratory testing on a rigid substrate. Tested constructions are available for critical fall heights of up to 300 cm; tile thickness alone does not demonstrate suitability.
Where the tested critical fall height is insufficient, a construction with a higher tested fall height, a lower free height of fall or different equipment design is required. On site, the construction must match the tested specification. Impact-absorbing safety surfacing tiles are installed in accordance with the installation requirements on a level, load-bearing substrate. Voids, settlement and open joints reduce shock absorption.
Loose-fill materials must be installed at the required depth, with an allowance for displacement. Hollows can develop quickly at the base of the wall, so fill level and distribution require regular checking and replenishment. The impact area must not contain foundations, edges or other hard objects. Sport climbing walls and bouldering walls are separate from this category and, depending on their construction and use, fall under BS EN 12572; surfacing tested to BS EN 1177 does not replace a safety system. Climbing walls may require rope belay systems or auto-belays, while bouldering walls require an impact-mat construction designed to BS EN 12572.